confirmation hearings began for massachusetts senator john kerry, who is expected to easily secure the nomination. but yesterday, clinton was the star of a much more contentious hearing. here's abc's martha raddatz. >> reporter: it was a riveting drama. secretary of state clinton, seemed in rare public form. at times, angry. aggressively on the defense. at another point, choking up over her four, lost colleagues. >> i put my arms around the mothers and fathers, the sisters and brothers, the sons and daughters. and the wives left alone to raise their children. >> the american people and the families of these four, brave americans still have not gotten the answers that they deserve. i hope that they will get them. >> reporter: and the secretary did not hesitate to shoulder the blame. >> as i have said many times, i take responsibility. >> reporter: but she insisted she never saw any of the requests for more security in the run-up to the attack. >> they didn't come to me. i didn't approve them. i didn't deny them. >> reporter: that made republican senators pounce. >> i think it's inexcusa